1. Field of the Invention
The present invention generally relates a vehicle body frame of a motorcycle that can support an engine while reducing the number of parts.
2. Description of the Related Art
Racing motorcycles must possess a high degree of frame rigidity, as do motorcycles styled after such racing motorcycles. Accordingly, there recently has been proposed a split motorcycle body frame. The frame includes a pair of main frames that are split into left and right sides from a steering head pipe. The pair of main frames extend rearwardly and downwardly from that location. A pair of left and right rear arm brackets extend downwardly from rear ends of the respective main frames. The steering head pipe also is split into left and right split steering head pipes. The left and right split steering head pipes, the left and right main frames and the left and right rear arm brackets are integrated into left and right split frames (see, for example, JP-A-63-315384, pages 1-5 and FIG. 3).
In such a split frame construction, the left and right split frames are connected together using a cross member and an engine is suspended on the pair of left and right split frames. Accordingly, the number of parts used during construction is increased due to the need for the cross member. The increase in parts and the associated manufacturing steps results in increased manufacturing costs. Moreover, the increased number of parts results in an increased weight for the frame.